Cardiorespiratory parameter | Singing repertoire (component 6) median (IQR) | Baseline rest period 1 | Difference from singing repertoire (p value*) | Walking at 2 km/hour median (IQR) | Difference from singing repertoire (p value*) | Walking at 4 km/hour median (IQR) | Difference from singing repertoire (p value*) | Walking at 6 km/hour median (IQR) | Difference from singing repertoire (p value*) |
Median (IQR) | |||||||||
VO2 mL/kg/min | 16.27 (10.74–18.86) | 3.95 (3.69–4.35) | −12.32 (0.012) | 8.19 (7.26–9.01) | −8.08 (0.012) | 10.42 (9.68–11.33) | −5.85 (0.036) | 15.39 (14.68–16.64) | −0.88 (1.00) |
METs | 4.12 (2.72–4.78) | 1.00 (0.93–1.10) | −3.12 (0.012) | 2.07 (1.84–2.28) | −2.05 (0.012) | 2.64 (2.45–2.87) | −1.48 (0.036) | 3.90 (3.72–4.21) | −0.22 (1.00) |
End tidal CO2 kPa | 5.16 (4.91–5.51) | 4.24 (3.80–4.52) | −0.92 (<0.05) | 4.43 (3.88–4.45) | −0.73 (<0.05) | 4.62 (4.08–4.91) | −0.54 (0.069) | 4.91 (4.40–5.14) | −0.25 (0.12) |
Heart rate (bpm) | 108 (97–114) | 76 (63–82) | −31 (0.012) | 86 (81–91) | −22 (0.012) | 99 (88–107) | −9 (0.042) | 108 (101–119) | 0 (0.62) |
Minute ventilation (L/min) | 22.42 (16.83–30.54) | 11 (9–13) | −10.9 (0.012) | 18.77 (16.89–21.35) | −3.72 (0.069) | 23.27 (20.09–26.37) | +0.85 (0.89) | 30.35 (26.94–41.11) | +7.93 (0.017) |
Respiratory rate (breaths/min) | 10 (7–13) | 15 (14–17) | +5.35 (0.017) | 23 (21–29) | +12.75 (0.012) | 23 (20–31) | +12.49 (0.012) | 24 (20–35) | +13.32 (0.012) |
Volume per breath (L/breath) | 2.11 (1.92–2.70) | 0.69 (0.63–0.77) | −1.42 (0.0117) | 0.80 (0.68–0.98) | −1.31 (0.012) | 0.93 (0.86–1.05) | −1.18 (0.012) | 1.21 (1.09–1.43) | −0.90 (0.012) |
Borg Dyspnoea Scale | 1.0 (1.0–2.5) | 0 (0–0) | −1 (0.013) | 0.00 (0.00–0.50) | −1 (0.019) | 0.75 (0.50–1.00) | −0.25 (0.049) | 1.00 (0.75–1.00) | 0 (0.049) |
Borg Rating of Perceived Exertion Scale | 8.5 (8.0–9.0) | 6 (6–6) | −2.5 (0.019) | 6.00 (6.00–7.00) | −2.5 (0.035) | 7.50 (7.00–8.00) | −1 (0.052) | 9.00 (8.00–9.00) | +0.5 (0.8788) |
*Wilcoxon signed-rank test. Data are provided to two decimal places, or less, when appropriate for degree of accuracy of the specific measurement.
bpm, beats per minute; CO2, carbon dioxide; METs, metabolic equivalents; VO2, oxygen consumption.